Interstellar Astrochemistry

有了这个奖项，埃里克·赫布斯特博士将继续他的天体化学项目，研究宇宙中分子的作用，它们是在哪里被发现的，它们是如何产生和毁灭的，以及它们告诉我们银河系和其他星系中无数不同来源的信息。他特别感兴趣的是对分子的观察所得出的关于恒星形成过程的信息。我们对星际介质的了解大多是通过对分子光谱的观察得来的，可以通过分析分子光谱来确定分子的丰度。然而，这些丰度意味着什么？为了充分理解分子告诉我们它们所处物体的现在和过去，有必要了解分子是如何形成和破坏的，以及这些形成和破坏过程是如何依赖于物理条件（如温度和密度）以及来源的历史的。为了理解分子的产生和消耗，已经建立了大型化学反应网络，包括气相和颗粒表面过程。这些化学网络与源的物理模型一起使用，无论是均匀的还是非均匀的，都允许建模者计算气体和尘埃颗粒表面的分子丰度。与观测数据的成功比较可以给我们提供有关源的物理条件和寿命的信息。本项目的研究建立在实验室早期工作的基础上，主要关注恒星形成的过程，这导致了各种不同的表现和阶段。通过对分子光谱的研究，就像通过化学计算的棱镜分析一样，人们可以开始瞥见恒星形成时气体和尘埃发生了什么。赫布斯特博士在天体化学方面的工作对分子作为星际介质探测器的迅速应用起到了重要作用。从60年代末和70年代初开始，分子天文学领域已经成为一项世界性的努力，观测天文学家、理论化学家、实验科学家和建模者在共同感兴趣的问题上进行合作。现在，关于弥散和稠密星际云，尤其是恒星形成的大部分知识，都来自于对这些区域分子所告诉我们的信息的理解。此外，研究星际云中复杂分子的合成本身就是一个有趣的领域，显然与生物学的发展有关。除了继续进行天体化学的研究项目外，赫布斯特博士还试图通过发表评论文章、接受杂志和报纸的采访，以及到当地的小学、初中和高中讨论分子宇宙，使其他领域的科学家和普通公众都了解这个领域。去年，俄亥俄州立大学创建了一个特殊的天体化学跨学科项目，由赫布斯特博士领导，他将于每年6月在俄亥俄州哥伦布市举办一次天体化学小型会议，作为更大的光谱学研讨会的一部分

With this award, Dr. Eric Herbst will continue a program in astrochemistry, which is the study of the role of molecules in the universe, where they are found, how they are created and destroyed,and what they tell us about the myriad of different sources in our galaxy and others. In particular he is especially interested in what information observations of molecules yield about the process of star formation. Much of what we know about the interstellar medium is learned by observations of molecular spectra, which can be analyzed to determine molecular abundances. Yet what do these abundances signify? In order to understand fully what molecules are telling us about the present and past of the objects in which they reside, it is necessary to comprehend how the molecules are formed and destroyed, and how these formation and destruction processes depend on physical conditions such as temperature and density as well as the history of the sources. To understand molecular creation and depletion, large networks of chemical reactions have been created, including both gas phase and grain-surface processes. Used with physical models of sources, either homogeneous or heterogeneous, these chemical networks allow the modeler to calculatemolecular abundances, both in the gas and on the surfaces of dust grains. Successful comparison with observational data then gives us information on physical conditions and lifetimes of sources. The studies in this project build on earlier work from the laboratory, and are mainly concerned with the process of star formation, which leads to a large variety of different manifestations and stages. Through the study of molecular spectra, as analyzed through the prism of chemical calculations, one can begin to glimpse what is happening to gas and dust as stars form. Dr. Herbst's work in astrochemistry has been instrumental in the burgeoning use of molecules as probes of the interstellar medium. From its beginnings in the late 60s and early 70s, the field of molecular astronomy has become a world-wide endeavor in which observational astronomers, theoretical chemists, experimental scientists, and modelers collaborate on problems of mutual interest. Much of the knowledge of diffuse and dense interstellar clouds, and especially star formation, now comes from an understanding of what molecules in these regions are telling us. Moreover, the study of the synthesis of complex molecules in interstellar clouds is aninteresting field on its own and is clearly relevant to the development of biology. In addition to continuing a research program in astrochemistry, Dr. Herbst has tried to make the field known to both scientists in other fields and to the lay public by publishing review articles, giving interviews for magazines and newspapers, and by going to local elementary, middle, and high schools to discuss the molecular universe. In the last year, The Ohio State University has created a special interdisciplinary Program in Astrochemistry to be headed by Dr. Herbst, and he will run a mini-conference on astrochemistry each June as part of the larger spectroscopy symposium held in Columbus, Ohio.***